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Equation 126 · Part 1 · The Bend an Elevator Cannot Fake

Symbol Phi

Φ\Phi
Φ\Phi

What this part means

Phi is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.

Its job in the formula

Phi is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.

The passage around this formula

For Earth modelled as a point mass, Φ(r)\Phi(r) = -GM/r gives a radial second derivative of magnitude 2GM/R3R^3 and, since Φ\Phi is harmonic in vacuum, transverse second derivatives of magnitude GM/R3R^3 with the opposite sign — a trace-free tensor in the exact ratio 2:{-1}:{-1} . With the standard gravitational parameter GM⊕M_\oplus =…

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